Katsuo is a secretive and serious person who does not like answering questions regarding his talent. Despite his reluctance to reveal his talent and somewhat gruff nature, Katsuo is willing to help the others with their investigations and is a large player in the other class trials, and could be considered a fatherly type to Takumi as well as the others. Katsuo has a quirk where he refers to most of the other campers as “Kid”. He states that this isn’t meant to belittle them as much as it is a personal tic he picks up from his own father.  He speaks quite bluntly and informally.

Katsuo is one of the students that is suspicious of people, as well as the environment around him. He takes the situations he is in, even if not dangerous, very seriously, almost to the point of it being comical. Katsuo frequently makes attempts to lead the group of students and take control. Although it may take some time to build his trust, when he does trust someone, he is incredibly loyal and treats them with great respect.